Extreme cold even though we feel like it’s normal for us since we live in quite frigid areas is bad for your skin and the skin being rich in moisture, it can freeze and crack leading to the condition known as frostbite. Frostbite has the skin and in too extreme situations, even the underlying muscles freezing, effectively killing them resulting in a very painful medical condition. Keep skin covered and if possible, stay indoors and avoid exposure in the first place. Anybody who has had frostbite knows the pain it can cause and the loss of skin that can result. The blackened skin is in fact dead and will have to be taken out to allow healthy skin to grow back if possible. If damage goes in too deep that the re-generative tissue is damaged itself, all damaged tissue is removed to prevent gangrene or tissue rot wherein dead tissue decays releasing toxins into the body as it does.
Wind is a hidden danger of extremely cold weather for it has the nasty ability to be colder, taking moisture away from the skin. Wind chill is in fact colder than the actual surface temperature of the land so windbreakers above your winter jacket would be nice to keep it out. We humans were not designed for extremely cold weather which makes it vital for us to get proper protection from such cold temperatures, enough to keep moisture in yet breathable enough to get moisture out, keeping it out far from your skin where it can freeze.